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D Craufurd

Publications and source records attributed to D Craufurd.

At least 19 recordsLinked to original sources
PubMed2003

Social cognition in frontotemporal dementia and Huntington's disease.

Frontotemporal dementia (FTD) and Huntington's disease (HD) are degenerative disorders, with predominant involvement, respectively of frontal neocortex and striatum. Both conditions give rise to altered social conduct and breakdown in interpersonal relationships, although the factors underlying these changes remain poorly defined. The study used tests of theory of mind (interpretation of cartoons and stories and judgement of preference based on eye gaze) to explore the ability of patients with FTD and HD to interpret social situations and ascribe mental states to others. Performance in the FTD group was severely impaired on all tasks, regardless of whether the test condition required attribution of a mental state. The HD group showed a milder impairment in cartoon and story interpretation, and normal preference judgements. Qualitative differences in performance were demonstrated between groups. FTD patients made more concrete, literal interpretations, whereas HD patients were more likely to misconstrue situations. The findings are interpreted as demonstrating impaired theory of mind in FTD, as one component of widespread executive deficits. In HD the evidence does not suggest a fundamental loss of theory of mind, but rather a tendency to draw faulty inferences from social situations. It is concluded that social breakdown in FTD and HD may have a different underlying basis and that the frontal neocortex and striatum have distinct contributions to social behaviour.

Cognition↗
PubMed2002

Psychomotor, executive, and memory function in preclinical Huntington's disease.

The earliest changes in the development of Huntington's disease (HD) remain controversial. Studies of cognitive function in preclinical individuals who have the HD mutation have yielded contradictory results. This study compared cognitive and motor performance in 51 people with the HD mutation who had no clinical signs of HD, 85 at-risk individuals without the HD mutation and 43 individuals in the early stages of HD. Whereas highly significant differences were detected between the preclinical and early-HD groups, only subtle impairments were present in at-risk individuals with the HD mutation compared to those with normal HD alleles, principally for low-demand psychomotor tasks. Complementing these observations, longitudinal investigation showed that performance on psychomotor tasks in people with the mutation who were close to clinical onset of HD was intermediate between that of individuals many years from onset and those in the early stages of HD, suggesting a slowly insidious evolution of deficit. In contrast, memory performance showed a more precipitous decline around the time of clinical onset of HD. The findings, which suggest that HD patients' functional deficits do not evolve uniformly, help to resolve some of the disparities in the literature on preclinical HD.

Adult↗
PubMed2002

Inherited frontotemporal dementia in nine British families associated with intronic mutations in the tau gene.

Genetic screening of 171 patients with frontotemporal lobar degeneration disclosed 14 patients, across nine pedigrees, with mutations in the intron to exon 10 in the tau gene, a region regulating the splicing of exon 10 via a stem loop mechanism. Thirteen of these patients had the +16 splice site mutation and one had the +13 splice site mutation. Affected members of all nine families presented with changes in behaviour and social conduct that were prototypical of frontotemporal dementia (FTD). In all patients with the +16 splice site mutation, the behavioural profile was characterized by disinhibition, restless overactivity, a fatuous affect, puerile behaviour and verbal and motor stereotypies. The single patient with the +13 mutation presented a contrasting picture of apathy and inertia. In addition, all patients had evidence of semantic loss. Pathologically, five of the six patients so far autopsied shared frontotemporal atrophy with involvement of the substantia nigra. The underlying histology was that of microvacuolar-type cortical degeneration with a few swollen cells. Tau pathology was widespread throughout the brain and present in neurones and glial cells, mostly in the frontal and temporal cortical regions. This was in the form of neurofibrillary tangles and amorphous tau deposits (pre-tangles); Pick bodies were not observed. Ultrastructurally, the tau filaments had a twisted, ribbon-like morphology distinct from the paired helical filaments of Alzheimer's disease. One patient died from an unrelated illness whilst in the early clinical stages of FTD. In this patient, cortical microvacuolar and astrocytic changes were absent, though there were scattered neurones and glial cells, immunoreactive to tau, throughout the cortical and subcortical regions. The disease process underlying the neurodegeneration within these inherited forms of FTD may therefore stem directly from early, primary alterations in the function of tau. All eight families with the +16 mutation seem to be part of a common extended pedigree, possibly originating from a founder member residing within the North Wales region of Great Britain.

Age of Onset↗
PubMed2002

Comparison of genetic services with and without genetic registers: knowledge, adjustment, and attitudes about genetic counselling among probands referred to three genetic clinics.

Genetic register services incorporating long term follow up and a proactive approach to at risk subjects have been recommended as a way of improving access to genetic counselling for families with dominant or X linked genetic disorders and chromosome translocations. The aims of the present study were to evaluate the psychosocial benefits and drawbacks of long term family contact, and to evaluate the attitudes of probands and their general practitioners towards proactive genetic counselling. We interviewed 192 people referred to three regional genetic clinics because of a family history of Duchenne or Becker muscular dystrophy, myotonic dystrophy, or chromosome translocations, and 43 of the referring GPs. Probands attending the centre using a genetic register approach were compared with those from the two centres offering the standard clinical genetic service. A very high proportion of probands in both groups were well informed about the genetic risks to themselves and their children, were satisfied with the service they had received from their local genetic clinic, and felt adequately prepared to discuss the family illness with their children. The register probands expressed approval of the ongoing contact and open access provided by the register service. Asked whether previously unaware relatives should be informed of their at risk status, 98% (188/192) said it was acceptable for this information to be disclosed by a family member, while three quarters of the probands (149/192) and just over half the GPs (27/43) thought it acceptable for the genetic service to approach them; a similar proportion of both GPs and probands also found it acceptable for GPs to do so. More than half the probands (107/190) thought it was the family's responsibility to pass on genetic risk information, but 43% said that either the genetic service or the GP should be responsible for this. The findings show that the genetic register approach incorporating long term follow up and a proactive approach to genetic counselling is highly acceptable to the families concerned, and although the register and non-register probands did not differ significantly on any of the main outcome measures used in this relatively short term study, it may be that the continuing contact associated with the register approach offers long term benefits, especially for those genetic conditions where medical surveillance may have an impact on the prognosis.

Adult↗
PubMed2002

Comparison of genetic services with and without genetic registers: access and attitudes to genetic counselling services among relatives of genetic clinic patients.

The pedigrees of 192 subjects at risk of Duchenne or Becker muscular dystrophy, myotonic dystrophy, or balanced chromosome translocations attending three regional genetic clinics were inspected to identify relatives who were themselves at high risk of these disorders. Of the 342 relatives eligible for inclusion, 43% (63/147) of the register relatives and 26% (50/195) of the non-register relatives had had contact with the clinical genetic services, a significant difference (p<0.02). Relatives from families with muscular dystrophy were significantly more likely to have been in contact with genetic services than those from BT families. Fifty-two relatives were interviewed about their experience and attitudes regarding genetic counselling. Almost all regarded knowledge about the family genetic disorder as helpful, and only one thought it unacceptable for relatives to be informed that they are at risk; 94% thought it was acceptable for this information to come from family members, 92% from general practitioners, and 90% from the clinical genetic service. A majority of relatives (53%) thought it was the family's responsibility to pass on genetic risk information, but 22% said the genetic service should be responsible and 18% thought it should be the GP. These data, together with the findings from the study of probands attending genetic clinics for these disorders, indicate that the genetic register approach incorporating long term follow up and a proactive approach to genetic counselling is acceptable to the families concerned and improves access to genetic services for at risk relatives.

Adult↗
PubMed2001

Longitudinal evaluation of cognitive disorder in Huntington's disease.

The study investigated longitudinal change in cognitive function in 87 patients with Huntington's disease (HD), using a range of neuropsychological tests, which tap mental manipulative abilities, memory, and frontal executive skills. Over a 1-year period the largest changes were noted in letter fluency, object recall, and Stroop Test performance, whereas no changes were noted over more than 3 years on the modified Wisconsin Card Sorting Test. Contrary to expectation, greater change was evident over 1 year for tasks with low compared to high cognitive demands. The differential sensitivity of tasks was attributed in part to inherent characteristics of the tests themselves: their capacity to detect minor gradations of change and their vulnerability to practice effects. However, the greater change for relatively automatic, speed-based tasks with low cognitive demands was interpreted as reflecting the evolution of HD, with a greater magnitude of change occurring in basal ganglia than cortical function. One purpose of the study was to identify tasks sensitive to the progression of HD and hence most suitable for the evaluation of therapies. Despite reaching statistical significance by virtue of the large group size, numerical differences in test scores over 1 year were very small, suggesting that the use of such tests to evaluate change in individuals or small groups of subjects would be problematic. The data highlight the slow progression of HD, the limitations of standard cognitive tests in detecting change over short periods, and the need for therapeutic studies that encompass a relatively prolonged time frame.

Adult↗
PubMed2000

Ten years of presymptomatic testing for Huntington's disease: the experience of the UK Huntington's Disease Prediction Consortium.

Data on all presymptomatic genetic tests for Huntington's disease (HD) in the UK have been collected over the 10 year period since testing became available as a service. A total of 2937 completed tests have been performed up to the end of 1997, 2502 based on specific mutation testing, feasible since late 1993.A total of 93.1% of these were at 50% prior risk, with a significant excess of females (58.3%); 41.4% of results were abnormal or high risk, including 29.4% in subjects aged 60 or over. The trend in test numbers has currently levelled out at around 500 per year. Almost all presymptomatic tests are carried out in National Health Service genetics centres, with a defined genetic counselling protocol and with availability now in all regions of the UK. The introduction and establishment of HD presymptomatic testing shows that this form of predictive medicine for Mendelian disorders can be successfully incorporated into National Health Service structures. The comprehensive collection of simple data allows trends in demand and outcomes to be monitored and has also been the foundation for more detailed specific studies. A comparable approach to data collection in other genetic disorders will be important as presymptomatic testing becomes more generally feasible.

Female↗
PubMed1999

Frequency of tau mutations in three series of non-Alzheimer's degenerative dementia.

Splice-site and missense mutations have been identified in tau associated with frontotemporal dementia with parkinsonism linked to chromosome 17. In this study we assessed the genetic contribution of tau mutations to three patient series with non-Alzheimer's (non-AD) degenerative dementia. The groups included (1) a community-based dementia series from Minnesota, MN; (2) a referral series with clinicopathological tauopathy; and (3) a pathologically confirmed familial frontotemporal dementia series from Manchester, UK. Comparing the three clinical series: in the stringently diagnosed Manchester frontotemporal dementia series, tau mutations were present in 13.6% of cases (three splice-site mutations); in the clinicopathological referral series that used more general inclusion criteria, 3 cases with P301L mutations were observed, which represents a lower mutation frequency of 3.6% (9.4% in familial cases); in contrast, tau mutations were not detected in the Minnesota community-based dementia series, suggesting the occurrence of these mutations in dementia generally is rare (<0.2%). These data identify the prevalence of mutations in three different clinical settings and indicate that this figure is sensitive to the diagnostic criteria used in each patient series.

Adult↗
PubMed1999

A worldwide assessment of the frequency of suicide, suicide attempts, or psychiatric hospitalization after predictive testing for Huntington disease.

Prior to the implementation of predictive-testing programs for Huntington disease (HD), significant concern was raised concerning the likelihood of catastrophic events (CEs), particularly in those persons receiving an increased-risk result. We have investigated the frequency of CEs-that is, suicide, suicide attempt, and psychiatric hospitalization-after an HD predictive-testing result, through questionnaires sent to predictive-testing centers worldwide. A total of 44 persons (0.97%) in a cohort of 4,527 test participants had a CE: 5 successful suicides, 21 suicide attempts, and 18 hospitalizations for psychiatric reasons. All persons committing suicide had signs of HD, whereas 11 (52.4%) of 21 persons attempting suicide and 8 (44.4%) of 18 who had a psychiatric hospitalization were symptomatic. A total of 11 (84.6%) of 13 asymptomatic persons who experienced a CE during the first year after HD predictive testing received an increased-risk result. Factors associated with an increased risk of a CE included (a) a psychiatric history </=5 years prior to testing and (b) unemployed status. The frequency of CEs did not differ between those persons receiving results of predictive testing through linkage analysis in whom there was only changes in direction of risk and those persons receiving definitive results after analysis for the mutation underlying HD. These findings provide insights into the frequency, associated factors, and timing of CEs in a worldwide cohort of persons receiving predictive-testing results and, as such, highlight persons for whom ongoing support may be beneficial.

Cohort Studies↗
PubMed1998

Association of missense and 5'-splice-site mutations in tau with the inherited dementia FTDP-17.

Thirteen families have been described with an autosomal dominantly inherited dementia named frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17), historically termed Pick's disease. Most FTDP-17 cases show neuronal and/or glial inclusions that stain positively with antibodies raised against the microtubule-associated protein Tau, although the Tau pathology varies considerably in both its quantity (or severity) and characteristics. Previous studies have mapped the FTDP-17 locus to a 2-centimorgan region on chromosome 17q21.11; the tau gene also lies within this region. We have now sequenced tau in FTDP-17 families and identified three missense mutations (G272V, P301L and R406W) and three mutations in the 5' splice site of exon 10. The splice-site mutations all destabilize a potential stem-loop structure which is probably involved in regulating the alternative splicing of exon10. This causes more frequent usage of the 5' splice site and an increased proportion of tau transcripts that include exon 10. The increase in exon 10+ messenger RNA will increase the proportion of Tau containing four microtubule-binding repeats, which is consistent with the neuropathology described in several families with FTDP-17.

Alternative Splicing↗
PubMed1998

Awareness of involuntary movements in Huntington disease.

OBJECTIVE: To determine why patients with Huntington disease are apparently unaware of their involuntary movements. DESIGN: Correlative study using a subjective report questionnaire of physical symptoms and objective measures of neurologic and cognitive dysfunction. PATIENTS: Forty patients with Huntington disease attending a regional Huntington disease clinic. RESULTS: Patients were poor at reporting experiential symptoms of involuntary movements. There was no relationship between self-report of these symptoms and objective indices of motor dysfunction or severity of cognitive impairment. Patients could, however, report secondary consequences of their movement disorder, which correlated highly with nonchoreic indices of motor dysfunction. CONCLUSIONS: Patients with Huntington disease have impaired subjective experience of chorea. Denial of symptoms is likely to have a physiological basis and is not a secondary consequence of patients' cognitive impairment or a psychological defense against a debilitating disease.

Adaptation, Psychological↗
PubMed1997

Genotypes at the GluR6 kainate receptor locus are associated with variation in the age of onset of Huntington disease.

Huntington disease (HD) is associated with abnormal expansions of a CAG repeat close to the 5' end of the IT15 gene. We have assembled a set of 293 HD subjects whose ages of onset were known and sized their HD CAG repeats. These repeats accounted for 69% of the variance of age of onset when we used the most parsimonious model, which relates the logarithm of age of onset to a function of CAG repeat number. Since other familial factors have been proposed to influence the age of onset of HD, we have examined a number of candidate loci. The CAG repeat number on normal chromosomes, the delta2642 polymorphism in the HD gene, and apolipoprotein E genotypes did not affect the age of onset of HD. Although mitochondrial energy production defects in HD have led to suggestions that variants in the mitochondrial genome may be associated with clinical variability in HD, this suggestion was not supported by our preliminary experiments that examined the DdeI mitochondrial restriction fragment length polymorphism at position 10,394. Excitotoxicity has been a favored mechanism to explain the cell death in HD, particularly since intrastriatal injection of excitatory amino acids in animals creates HD-like pathology. Accordingly, we investigated the GluR6 kainate receptor. Of the variance in the age of onset of HD that was not accounted for by the CAG repeats, 13% could be attributed to GluR6 genotype variation. These data implicate GluR6-mediated excitotoxicity in the pathogenesis of HD and highlight the potential importance of this process in other polyglutamine repeat expansion diseases.

Adult↗
PubMed1997

The uptake and acceptability to patients of cystic fibrosis carrier testing offered in pregnancy by the GP.

OBJECTIVE: To determine the uptake and acceptability of cystic fibrosis (CF) carrier testing when offered to women at the first antenatal booking appointment by their general practitioner. SETTING: Eight-general practices in the north west region with a combined patient list size of 42000. DESIGN: Offer of carrier screening at first antenatal booking appointment to pregnant women below 14 weeks' gestation; women accepting were alternately allocated to either couple testing (with full disclosure) or stepwise testing: SUBJECTS: Six hundred and twenty three women were offered CF carrier testing. MAIN OUTCOME MEASURES: (1) Acceptance of the offer of CF carrier testing. (2) Acceptability of the test to women following screening, evaluated through (i) postal questionnaire, (ii) semistructured interview. RESULTS: Five hundred and twenty-nine (84.9%) women accepted the test; the level of uptake varied across the eight practices (range 11-99%). In 26/249 (10%) couple tests no paternal sample was provided. When asked what had influenced their decision to be tested, 59/377 (16%) women did not refer to CF in their answers and six (2%) said that they did not feel they could refuse the test. After receiving their results, 368/379 (97%) women felt that they had made the right decision to be tested, but two carriers and three non-carriers had felt unhappy about testing. Couple testing with full disclosure was associated with lower anxiety levels two weeks after receiving the result for the pregnancy than stepwise testing and 82/278 (29%) non-carriers believed that they had no residual risk in relation to CF. CONCLUSIONS: The response from women accepting CF carrier testing was largely positive but a minority of women expressed concern about the test and the way it was offered and a substantial proportion of women were falsely reassured by their "negative" result. Higher levels of acceptance tended to occur in the practices which offered the test there and then rather than giving couples more time to decide about testing. Some women appeared to have accepted the test because of a belief in the importance of testing in pregnancy rather than because of the disease in question.

Adolescent↗
PubMed1997

Uptake of genetic testing for cancer predisposition.

Although there has been much debate about the uptake and effects of predictive testing for common cancers, such as breast and colon cancer, little has been published on the more classical tumour predisposing conditions, such as von Hippel-Lindau disease and familial adenomatous polyposis. Since 1990 the genetics departments in Manchester and Cambridge have had a genetic register for cancer predisposing syndromes and presymptomatic testing for these conditions has been offered once this has become possible. To investigate the factors that might influence uptake of genetic testing in familial cancer syndromes we have reviewed our experience. Demand for predictive testing has generally been high, but men had a lower uptake (77%) than a comparable group of women (93%) (p < 0.01).

Adenomatous Polyposis Coli↗
PubMed1997

Homozygotes and heterozygotes for ciliary neurotrophic factor null alleles do not show earlier onset of Huntington's disease.

The CAG repeat number on Huntington's disease (HD) chromosomes accounts for about 60% of the variance in the age at onset of HD. However, distinct familial factors may also influence the age at onset. HD is associated with loss of medium-sized GABA-ergic striatal output neurons. Intracerebral administration of human ciliary neurotrophic factor (CNTF) protects striatal output neurons in excitotoxic rodent and primate models of HD induced by intrastriatal quinolinic acid injection. We have examined the effect of a common null mutation in the human CNTF gene on the age of onset of HD using a multiple regression approach that takes into account the CAG repeat number on HD chromosomes. We failed to detect an earlier onset of HD in nine homozygotes and 71 heterozygotes with this CNTF mutation compared with 203 homozygotes with wild-type alleles.

Age of Onset↗
PubMed1996

Huntington's disease.

Huntington's disease (HD) is a late-onset degenerative disorder of the central nervous system, caused by a dominantly inherited mutation in a gene on chromosome 4p. The identification of the trinucleotide repeat mutation responsible for this disorder has been an important step towards understanding the molecular pathology of HD, but in the meantime has also made it possible to offer predictive testing and prenatal diagnosis to individuals at high genetic risk. Predictive testing offers obvious benefits for those who receive a favourable result, but also runs the risk of significant psychological and social problems for the families involved. Uptake of testing to date has been limited. Prenatal testing where the pregnancy is at 25% risk carries the same disadvantages as adult predictive testing, because an unfavourable result would also establish that the at-risk parent is a gene carrier; prenatal exclusion testing offers an alternative method of detecting and terminating at-risk pregnancies without revealing the genetic status of the at-risk parent.

Female↗
PubMed1996

Core Assessment Program for Intracerebral Transplantation in Huntington's Disease (CAPIT-HD).

Studies in Parkinson's disease using the Core Assessment Program for Intracerebral Transplantation (CAPIT) protocol have demonstrated that grafts of embryonic mesencephalic cells into striatum can survive, grow, and exert useful clinical effects. Attention in now being directed toward neural grafting in other conditions, such as Huntington's disease. As a precondition for grafting of embryonic striatal cells into diseased striatum in this complex motor and psychiatric disorder, not only is further basic research needed, but also a thorough and wide-ranging assessment protocol is essential. This article presents such a CAPIT-HD assessment protocol.

Animals↗